|
Records |
Links |
|
Author |
de Backer, A.; De wael, A.; Gonnissen, J.; Van Aert, S. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Optimal experimental design for nano-particle atom-counting from high-resolution STEM images |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
151 |
Issue |
151 |
Pages |
46-55 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
In the present paper, the principles of detection theory are used to quantify the probability of error for atom-counting from high resolution scanning transmission electron microscopy (HR STEM) images. Binary and multiple hypothesis testing have been investigated in order to determine the limits to the precision with which the number of atoms in a projected atomic column can be estimated. The probability of error has been calculated when using STEM images, scattering cross-sections or peak intensities as a criterion to count atoms. Based on this analysis, we conclude that scattering cross-sections perform almost equally well as images and perform better than peak intensities. Furthermore, the optimal STEM detector design can be derived for atom-counting using the expression for the probability of error. We show that for very thin objects LAADF is optimal and that for thicker objects the optimal inner detector angle increases. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000351237800007 |
Publication Date |
2014-11-11 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
24 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
312483 Esteem2; Fwo G039311; G037413; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2015 IF: 2.436 |
|
|
Call Number |
c:irua:123926 c:irua:123926 |
Serial |
2481 |
|
Permanent link to this record |
|
|
|
|
Author |
Guzzinati, G.; Clark, L.; Béché, A.; Juchtmans, R.; Van Boxem, R.; Mazilu, M.; Verbeeck, J. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Prospects for versatile phase manipulation in the TEM : beyond aberration correction |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
151 |
Issue |
151 |
Pages |
85-93 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
In this paper we explore the desirability of a transmission electron microscope in which the phase of the electron wave can be freely controlled. We discuss different existing methods to manipulate the phase of the electron wave and their limitations. We show how with the help of current techniques the electron wave can already be crafted into specific classes of waves each having their own peculiar properties. Assuming a versatile phase modulation device is feasible, we explore possible benefits and methods that could come into existence borrowing from light optics where the so-called spatial light modulators provide programmable phase plates for quite some time now. We demonstrate that a fully controllable phase plate building on Harald Rose׳s legacy in aberration correction and electron optics in general would open an exciting field of research and applications. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000351237800012 |
Publication Date |
2014-10-22 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
19 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
278510 Vortex; Fwo; 312483 Esteem2; esteem2jra2; esteem2jra3 ECASJO_; |
Approved |
Most recent IF: 2.843; 2015 IF: 2.436 |
|
|
Call Number |
c:irua:121405 c:irua:121405UA @ admin @ c:irua:121405 |
Serial |
2731 |
|
Permanent link to this record |
|
|
|
|
Author |
Martinez, G.T.; Rosenauer, A.; de Backer, A.; Verbeeck, J.; Van Aert, S. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Quantitative composition determination at the atomic level using model-based high-angle annular dark field scanning transmission electron microscopy |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
137 |
Issue |
|
Pages |
12-19 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
High angle annular dark field scanning transmission electron microscopy (HAADF STEM) images provide sample information which is sensitive to the chemical composition. The image intensities indeed scale with the mean atomic number Z. To some extent, chemically different atomic column types can therefore be visually distinguished. However, in order to quantify the atomic column composition with high accuracy and precision, model-based methods are necessary. Therefore, an empirical incoherent parametric imaging model can be used of which the unknown parameters are determined using statistical parameter estimation theory (Van Aert et al., 2009, [1]). In this paper, it will be shown how this method can be combined with frozen lattice multislice simulations in order to evolve from a relative toward an absolute quantification of the composition of single atomic columns with mixed atom types. Furthermore, the validity of the model assumptions are explored and discussed. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000331092200003 |
Publication Date |
2013-11-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
74 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
FWO; FP7; ERC Countatoms; ESTEEM2; esteem2_ta |
Approved |
Most recent IF: 2.843; 2014 IF: 2.436 |
|
|
Call Number |
UA @ lucian @ c:irua:111579UA @ admin @ c:irua:111579 |
Serial |
2749 |
|
Permanent link to this record |
|
|
|
|
Author |
Heidari, H.; van den Broek, W.; Bals, S. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Quantitative electron tomography : the effect of the three-dimensional point spread function |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
135 |
Issue |
|
Pages |
1-5 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
The intensity levels in a three-dimensional (3D) reconstruction, obtained by electron tomography, can be influenced by several experimental imperfections. Such artifacts will hamper a quantitative interpretation of the results. In this paper, we will correct for artificial intensity variations by determining the 3D point spread function (PSF) of a tomographic reconstruction based on high angle annular dark field scanning transmission electron microscopy. The large tails of the PSF cause an underestimation of the intensity of smaller particles, which in turn hampers an accurate radius estimate. Here, the error introduced by the PSF is quantified and corrected a posteriori. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000326941500001 |
Publication Date |
2013-06-21 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
6 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Esteem2; Sunflower; esteem2_jra4 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
|
|
Call Number |
UA @ lucian @ c:irua:111397 |
Serial |
2756 |
|
Permanent link to this record |
|
|
|
|
Author |
Martinez, G.T.; Jones, L.; de Backer, A.; Béché, A.; Verbeeck, J.; Van Aert, S.; Nellist, P.D. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Quantitative STEM normalisation : the importance of the electron flux |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
159 |
Issue |
159 |
Pages |
46-58 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Annular dark-field (ADF) scanning transmission electron microscopy (STEM) has become widely used in quantitative studies based on the opportunity to directly compare experimental and simulated images. This comparison merely requires the experimental data to be normalised and expressed in units of fractional beam-current. However, inhomogeneities in the response of electron detectors can complicate this normalisation. The quantification procedure becomes both experiment and instrument specific, requiring new simulations for the particular response of each instrument's detector, and for every camera-length used. This not only impedes the comparison between different instruments and research groups, but can also be computationally very time consuming. Furthermore, not all image simulation methods allow for the inclusion of an inhomogeneous detector response. In this work, we propose an alternative method for normalising experimental data in order to compare these with simulations that consider a homogeneous detector response. To achieve this, we determine the electron flux distribution reaching the detector by means of a camera-length series or a so-called atomic column cross-section averaged convergent beam electron diffraction (XSACBED) pattern. The result is then used to determine the relative weighting of the detector response. Here we show that the results obtained by this new electron flux weighted (EFW) method are comparable to the currently used method, while considerably simplifying the needed simulation libraries. The proposed method also allows one to obtain a metric that describes the quality of the detector response in comparison with the ideal detector response. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000366220000006 |
Publication Date |
2015-08-01 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
27 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
246791 Countatoms; 278510 Vortex; 312483 Esteem2; Fwo G036815; G036915; G037413; G004413; esteem2ta ECASJO; |
Approved |
Most recent IF: 2.843; 2015 IF: 2.436 |
|
|
Call Number |
c:irua:127293 c:irua:127293UA @ admin @ c:irua:127293 |
Serial |
2762 |
|
Permanent link to this record |
|
|
|
|
Author |
Lichtert, S.; Verbeeck, J. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Statistical consequences of applying a PCA noise filter on EELS spectrum images |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
125 |
Issue |
|
Pages |
35-42 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Principal component analysis (PCA) noise filtering is a popular method to remove noise from experimental electron energy loss (EELS) spectrum images. Here, we investigate the statistical behaviour of this method by applying it on a simulated data set with realistic noise levels. This phantom data set provides access to the true values contained in the data set as well as to many different realizations of the noise. Using least squares fitting and parameter estimation theory, we demonstrate that even though the precision on the estimated parameters can be better as the CramérRao lower bound, a significant bias is introduced which can alter the conclusions drawn from experimental data sets. The origin of this bias is in the incorrect retrieval of the principal loadings for noisy data. Using an expression for the bias and precision of the singular values from literature, we present an evaluation criterion for these singular values based on the noise level and the amount of information present in the data set. This criterion can help to judge when to avoid PCA noise filtering in practical situations. Further we show that constructing elemental maps of PCA noise filtered data using the background subtraction method, does not guarantee an increase in the signal to noise ratio due to correlation of the spectral data as a result of the filtering process. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000314679700006 |
Publication Date |
2012-10-27 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
54 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Fwo; Countatoms; Vortex; Esteem 312483; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
|
|
Call Number |
UA @ lucian @ c:irua:105293 |
Serial |
3153 |
|
Permanent link to this record |
|
|
|
|
Author |
Schattschneider, P.; Stöger-Pollach, M.; Löffler, S.; Steiger-Thirsfeld, A.; Hell, J.; Verbeeck, J. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Sub-nanometer free electrons with topological charge |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
115 |
Issue |
|
Pages |
21-25 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
The holographic mask technique is used to create freely moving electrons with quantized angular momentum. With electron optical elements they can be focused to vortices with diameters below the nanometer range. The understanding of these vortex beams is important for many applications. Here, we produce electron vortex beams and compare them to a theory of electrons with topological charge. The experimental results show excellent agreement with simulations. As an immediate application, fundamental experimental parameters like spherical aberration and partial coherence are determined. (C) 2012 Elsevier B.V. All rights reserved. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000302962400004 |
Publication Date |
2012-01-30 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
24 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
vortex ECASJO_; |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
|
|
Call Number |
UA @ lucian @ c:irua:98279 |
Serial |
3344 |
|
Permanent link to this record |
|
|
|
|
Author |
Lobato, I.; Van Aert, S.; Verbeeck, J. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Progress and new advances in simulating electron microscopy datasets using MULTEM |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
168 |
Issue |
168 |
Pages |
17-27 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
A new version of the open source program MULTEM is presented here. It includes a graphical user interface, tapering truncation of the atomic potential, CPU multithreading functionality, single/double precision calculations, scanning transmission electron microscopy (STEM) simulations using experimental detector sensitivities, imaging STEM (ISTEM) simulations, energy filtered transmission electron microscopy (EFTEM) simulations, STEM electron energy loss spectroscopy (EELS) simulations along with other improvements in the algorithms. We also present a mixed channeling approach for the calculation of inelastic excitations, which allows one to considerably speed up time consuming EFTEM/STEM-EELS calculations. |
|
|
Address |
EMAT, University of Antwerp, Department of Physics, Groenenborgerlaan 171, B-2020 Antwerp, Belgium |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Wos |
000380754100003 |
Publication Date |
2016-06-11 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
43 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483- ESTEEM2. The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N and G.0368.15N).; esteem2jra3; esteem2na3; esteem2_jra2 |
Approved |
Most recent IF: 2.843 |
|
|
Call Number |
c:irua:134088 c:irua:134088UA @ admin @ c:irua:134088 |
Serial |
4093 |
|
Permanent link to this record |
|
|
|
|
Author |
Muller-Caspary, K.; Krause, F.F.; Grieb, T.; Loffler, S.; Schowalter, M.; Béché, A.; Galioit, V.; Marquardt, D.; Zweck, J.; Schattschneider, P.; Verbeeck, J.; Rosenauer, A. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Measurement of atomic electric fields and charge densities from average momentum transfers using scanning transmission electron microscopy |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
178 |
Issue |
178 |
Pages |
62-80 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
This study sheds light on the prerequisites, possibilities, limitations and interpretation of high-resolution differential phase contrast (DPC) imaging in scanning transmission electron microscopy (STEM). We draw particular attention to the well-established DPC technique based on segmented annular detectors and its relation to recent developments based on pixelated detectors. These employ the expectation value of the momentum transfer as a reliable measure of the angular deflection of the STEM beam induced by an electric field in the specimen. The influence of scattering and propagation of electrons within the specimen is initially discussed separately and then treated in terms of a two-state channeling theory. A detailed simulation study of GaN is presented as a function of specimen thickness and bonding. It is found that bonding effects are rather detectable implicitly, e.g., by characteristics of the momentum flux in areas between the atoms than by directly mapping electric fields and charge densities. For strontium titanate, experimental charge densities are compared with simulations and discussed with respect to experimental artifacts such as scan noise. Finally, we consider practical issues such as figures of merit for spatial and momentum resolution, minimum electron dose, and the mapping of larger-scale, built-in electric fields by virtue of data averaged over a crystal unit cell. We find that the latter is possible for crystals with an inversion center. Concerning the optimal detector design, this study indicates that a sampling of 5mrad per pixel is sufficient in typical applications, corresponding to approximately 10x10 available pixels. |
|
|
Address |
Institut fur Festkr perphysik, Universitat Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Wos |
000403862900009 |
Publication Date |
2016-05-12 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
93 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
K.M.-C. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG) under contract MU3660/1-1. This work was further supported by the DFG under contract RO2057/4-2 and O2057/11-1. J.V. and A.B. acknowledge funding from the European Research Council (ERC) under the 7th Framework Program (FP7), and ERC Starting Grant No. 278510-VORTEX. Experimental results are obtained on the Qu-Ant-EM microscope partly funded by the Hercules fund from the Flemish government. J.V. also acknowledges funding through a GOA project “Solarpaint” of the University of Antwerp. SL and PS acknowledge financial support by the Austrian Science Fund (FWF) under grants No. I543-N20 and J3732-N27. ECASJO_; |
Approved |
Most recent IF: 2.843 |
|
|
Call Number |
c:irua:134125UA @ admin @ c:irua:134125 |
Serial |
4098 |
|
Permanent link to this record |
|
|
|
|
Author |
Kirilenko, D.A.; Brunkov, P.N. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Measuring the height-to-height correlation function of corrugation in suspended graphene |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
165 |
Issue |
165 |
Pages |
1-7 |
|
|
Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
|
|
Abstract |
Nanocorrugation of 2D crystals is an important phenomenon since it affects their electronic and mechanical properties. The corrugation may have various sources; one of them is flexural phonons that, in particular, are responsible for the thermal conductivity of graphene. A study of corrugation of just the suspended graphene can reveal much of valuable information on the physics of this complicated phenomenon. At the same time, the suspended crystal nanorelief can hardly be measured directly because of high flexibility of the 2D crystal. Moreover, the relief portion related to rapid out-of-plane oscillations (flexural phonons) is also inaccessible by such measurements. Here we present a technique for measuring the Fourier components of the height-height correlation function H(q) of suspended graphene which includes the effect of flexural phonons. The technique is based on the analysis of electron diffraction patterns. The H(q) is measured in the range of wavevectors q approximately 0.4-4.5nm(-1). At the upper limit of this range H(q) does follow the T/kappaq(4) law. So, we measured the value of suspended graphene bending rigidity kappa=1.2+/-0.4eV at ambient temperature T approximately 300K. At intermediate wave vectors, H(q) follows a slightly weaker exponent than theoretically predicted q(-3.15) but is closer to the results of the molecular dynamics simulation. At low wave vectors, the dependence becomes even weaker, which may be a sign of influence of charge carriers on the dynamics of undulations longer than 10nm. The technique presented can be used for studying physics of flexural phonons in other 2D materials. |
|
|
Address |
Ioffe Institute, Politekhnicheskaya ul. 26, 194021 St-Petersburg, Russia; ITMO University, Kronverksky pr. 49, 197101 St. Petersburg, Russia |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Wos |
000375946200001 |
Publication Date |
2016-03-28 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
|
|
|
Impact Factor |
2.843 |
Times cited |
3 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
D.K. thanks the RFBR (Grant no. 16-32-60165) for the partial support of this research. The work was carried out in part at the Joint Research Center “Material Science and Characterization in Advanced Technologies” (St-Petersburg, Russia) under the financial support from the Ministry of Education and Science of the Russian Federation (Agreement 14.621.21.0007, 04.12.2014, id RFMEFI62114X0007, the use of the Jeol JEM-2100F microscope) and at EMAT, Universiteit Antwerpen (Antwerpen, Belgium), (the use of the FEI Tecnai G2 microscope). |
Approved |
Most recent IF: 2.843 |
|
|
Call Number |
EMAT @ emat @ |
Serial |
4124 |
|
Permanent link to this record |
|
|
|
|
Author |
Gonnissen, J.; De Backer, A.; den Dekker, A.J.; Sijbers, J.; Van Aert, S. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Detecting and locating light atoms from high-resolution STEM images: The quest for a single optimal design |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
170 |
Issue |
170 |
Pages |
128-138 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
In the present paper, the optimal detector design is investigated for both detecting and locating light atoms from high resolution scanning transmission electron microscopy (HR STEM) images. The principles of detection theory are used to quantify the probability of error for the detection of light atoms from HR STEM images. To determine the optimal experiment design for locating light atoms, use is made of the so-called Cramer-Rao Lower Bound (CRLB). It is investigated if a single optimal design can be found for both the detection and location problem of light atoms. Furthermore, the incoming electron dose is optimised for both research goals and it is shown that picometre range precision is feasible for the estimation of the atom positions when using an appropriate incoming electron dose under the optimal detector settings to detect light atoms. |
|
|
Address |
Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. Electronic address: sandra.vanaert@uantwerpen.be |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Wos |
000386925500014 |
Publication Date |
2016-07-26 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
6 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15, G.0369.15 and G.0374.13) and a postdoctoral research grant to A. De Backer. The research leading to these results has also received funding from the European Union Seventh Framework Programme [FP7/2007-2013] under Grant agreement no. 312483 (ESTEEM2). The authors would also like to thank A. Rosenauer for providing access to the STEMsim software and Gerardo T. Martinez for fruitful discussions.; esteem2_jra2 |
Approved |
Most recent IF: 2.843 |
|
|
Call Number |
c:irua:135337 c:irua:135337 |
Serial |
4128 |
|
Permanent link to this record |
|
|
|
|
Author |
De Backer, A.; van den Bos, K.H.W.; Van den Broek, W.; Sijbers, J.; Van Aert, S. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
StatSTEM: An efficient approach for accurate and precise model-based quantification of atomic resolution electron microscopy images |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
171 |
Issue |
171 |
Pages |
104-116 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighbouring columns, enabling the analysis of a large field of view. For this algorithm, the accuracy and precision with which measurements for the atomic column positions and scattering cross-sections from annular dark field (ADF) STEM images can be estimated, has been investigated. The highest attainable precision is reached even for low dose images. Furthermore, the advantages of the model-based approach taking into account overlap between neighbouring columns are highlighted. This is done for the estimation of the distance between two neighbouring columns as a function of their distance and for the estimation of the scattering cross-section which is compared to the integrated intensity from a Voronoi cell. To provide end-users this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000389106200014 |
Publication Date |
2016-09-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
43 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0393.11, G.0064.10 and G.0374.13), a Ph.D. research grant to K.H.W. van den Bos, and a postdoctoral research grant to A. De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3). A. Rosenauer is acknowledged for providing the STEMsim program.; esteem2_jra2 |
Approved |
Most recent IF: 2.843 |
|
|
Call Number |
EMAT @ emat @ c:irua:135516 |
Serial |
4280 |
|
Permanent link to this record |
|
|
|
|
Author |
Lobato, I.; Van Dyck, D. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
MULTEM : a new multislice program to perform accurate and fast electron diffraction and imaging simulations using graphics processing units with CUDA |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
156 |
Issue |
156 |
Pages |
9-17 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
The main features and the GPU implementation of the MULTEM program are presented and described. This new program performs accurate and fast multislice simulations by including higher order expansion of the multislice solution of the high energy Schrodinger equation, the correct subslicing of the three-dimensional potential and top-bottom surfaces. The program implements different kinds of simulation for CTEM, STEM, ED, PED, CBED, ADF-TEM and ABF-HC with proper treatment of the spatial and temporal incoherences. The multislice approach described here treats the specimen as amorphous material which allows a straightforward implementation of the frozen phonon approximation. The generalized transmission function for each slice is calculated when is needed and then discarded. This allows us to perform large simulations that can include millions of atoms and keep the computer memory requirements to a reasonable level. (C) 2015 Elsevier B.V. All rights reserved. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000361001800003 |
Publication Date |
2015-04-28 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
32 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.843; 2015 IF: 2.436 |
|
|
Call Number |
UA @ lucian @ c:irua:127848 |
Serial |
4209 |
|
Permanent link to this record |
|
|
|
|
Author |
van den Bos, K.H.W.; Krause, F.F.; Béché, A.; Verbeeck, J.; Rosenauer, A.; Van Aert, S. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Locating light and heavy atomic column positions with picometer precision using ISTEM |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
172 |
Issue |
172 |
Pages |
75-81 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Recently, imaging scanning transmission electron microscopy (ISTEM) has been proposed as a promising new technique combining the advantages of conventional TEM (CTEM) and STEM [1]. The ability to visualize light and heavy elements together makes it a particularly interesting new, spatially incoherent imaging mode. Here, we evaluate this technique in term of precision with which atomic column locations can be measured. By using statistical parameter estimation theory, we will show that these locations can be accurately measured with a precision in the picometer range. Furthermore, a quantitative comparison is made with HAADF STEM imaging to investigate the advantages of ISTEM. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000390600200009 |
Publication Date |
2016-10-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
8 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0368.15N, G.0369.15N), and by a Ph.D. grant to K.H.W. van den Bos. The research leading to these results has received funding from the Deutsche Forschungsgemeinschaft under Contract No. RO 2057/4-2 and the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2. We thank Prof. G. Koster from the University of Twente for kindly providing us with the PbTiO3 test sample. |
Approved |
Most recent IF: 2.843 |
|
|
Call Number |
EMAT @ emat @ c:irua:136109UA @ admin @ c:irua:136109 |
Serial |
4288 |
|
Permanent link to this record |
|
|
|
|
Author |
Gonnissen, J.; De Backer, A.; den Dekker, A.J.; Sijbers, J.; Van Aert, S. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Atom-counting in High Resolution Electron Microscopy: TEM or STEM – that's the question |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
174 |
Issue |
174 |
Pages |
112-120 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
In this work, a recently developed quantitative approach based on the principles of detection theory is used in order to determine the possibilities and limitations of High Resolution Scanning Transmission Electron Microscopy (HR STEM) and HR TEM for atom-counting. So far, HR STEM has been shown to be an appropriate imaging mode to count the number of atoms in a projected atomic column. Recently, it has been demonstrated that HR TEM, when using negative spherical aberration imaging, is suitable for atom-counting as well. The capabilities of both imaging techniques are investigated and compared using the probability of error as a criterion. It is shown that for the same incoming electron dose, HR STEM outperforms HR TEM under common practice standards, i.e. when the decision is based on the probability function of the peak intensities in HR TEM and of the scattering cross-sections in HR STEM. If the atom-counting decision is based on the joint probability function of the image pixel values, the dependence of all image pixel intensities as a function of thickness should be known accurately. Under this assumption, the probability of error may decrease significantly for atom-counting in HR TEM and may, in theory, become lower as compared to HR STEM under the predicted optimal experimental settings. However, the commonly used standard for atom-counting in HR STEM leads to a high performance and has been shown to work in practice. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000403342200013 |
Publication Date |
2016-10-27 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
2 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
The authors gratefully acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15N, G.0369.15N, G.0374.13N, and WO.010.16N) and a postdoctoral grant to A. De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme [FP7/2007-2013] under Grant agreement no. 312483 (ESTEEM2). |
Approved |
Most recent IF: 2.843 |
|
|
Call Number |
EMAT @ emat @ c:irua:137102 |
Serial |
4315 |
|
Permanent link to this record |
|
|
|
|
Author |
Hofer, C.; Pennycook, T.J. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Reliable phase quantification in focused probe electron ptychography of thin materials |
Type |
A1 Journal Article |
|
Year |
2023 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
254 |
Issue |
|
Pages |
113829 |
|
|
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
|
|
Abstract |
Electron ptychography provides highly sensitive, dose efficient phase images which can be corrected for aberrations after the data has been acquired. This is crucial when very precise quantification is required, such as with sensitivity to charge transfer due to bonding. Drift can now be essentially eliminated as a major impediment to focused probe ptychography, which benefits from the availability of easily interpretable simultaneous Z-contrast imaging. However challenges have remained when quantifying the ptychographic phases of atomic sites. The phase response of a single atom has a negative halo which can cause atoms to reduce in phase when brought closer together. When unaccounted for, as in integrating methods of quantification, this effect can completely obscure the effects of charge transfer. Here we provide a new method of quantification that overcomes this challenge, at least for 2D materials, and is robust to experimental parameters such as noise, sample tilt. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
001071608700001 |
Publication Date |
2023-08-18 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.2 |
Times cited |
|
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
FWO, G013122N ; Horizon 2020 Framework Programme; Horizon 2020; European Research Council, 802123-HDEM ; European Research Council; |
Approved |
Most recent IF: 2.2; 2023 IF: 2.843 |
|
|
Call Number |
EMAT @ emat @c:irua:200272 |
Serial |
8987 |
|
Permanent link to this record |
|
|
|
|
Author |
Batenburg, K.J.; Bals, S.; Sijbers, J.; Kübel, C.; Midgley, P.A.; Hernandez, J.C.; Kaiser, U.; Encina, E.R.; Coronado, E.A.; Van Tendeloo, G. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
3D imaging of nanomaterials by discrete tomography |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
109 |
Issue |
6 |
Pages |
730-740 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
The field of discrete tomography focuses on the reconstruction of samples that consist of only a few different materials. Ideally, a three-dimensional (3D) reconstruction of such a sample should contain only one grey level for each of the compositions in the sample. By exploiting this property in the reconstruction algorithm, either the quality of the reconstruction can be improved significantly, or the number of required projection images can be reduced. The discrete reconstruction typically contains fewer artifacts and does not have to be segmented, as it already contains one grey level for each composition. Recently, a new algorithm, called discrete algebraic reconstruction technique (DART), has been proposed that can be used effectively on experimental electron tomography datasets. In this paper, we propose discrete tomography as a general reconstruction method for electron tomography in materials science. We describe the basic principles of DART and show that it can be applied successfully to three different types of samples, consisting of embedded ErSi2 nanocrystals, a carbon nanotube grown from a catalyst particle and a single gold nanoparticle, respectively. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000265816400005 |
Publication Date |
2009-02-01 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
220 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
|
|
Call Number |
UA @ lucian @ c:irua:74665 c:irua:74665 |
Serial |
12 |
|
Permanent link to this record |
|
|
|
|
Author |
Bertoni, G.; Verbeeck, J. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Accuracy and precision in model based EELS quantification |
Type |
A1 Journal article |
|
Year |
2008 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
108 |
Issue |
8 |
Pages |
782-790 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
We present results on model based quantification of electron energy loss spectra (EELS), focusing on the factors that influence accuracy and precision in determining chemical concentrations. Several sources of systematical errors are investigated. The spectrometer entrance aperture determines the collection angle, and the effects of its position with respect to the transmitted beam are investigated, taking into account the diffraction by the crystal structure. The effect of the orientation of the sample is tested experimentally and theoretically on SrTiO3, and finally, a simulated experiment on c-BN at different thicknesses confirms the superior results of the model based method with respect to the conventional method. A test on a set of experimental reference compounds is presented, showing that remarkably good accuracy can be obtained. Recommendations are given to achieve high accuracy and precision in practice. (C) 2008 Elsevier B.V. All rights reserved. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000258241900010 |
Publication Date |
2008-02-22 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
44 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.843; 2008 IF: 2.629 |
|
|
Call Number |
UA @ lucian @ c:irua:70550UA @ admin @ c:irua:70550 |
Serial |
42 |
|
Permanent link to this record |
|
|
|
|
Author |
Roelandts, T.; Batenburg, K.J.; Biermans, E.; Kübel, C.; Bals, S.; Sijbers, J. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Accurate segmentation of dense nanoparticles by partially discrete electron tomography |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
114 |
Issue |
|
Pages |
96-105 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
Accurate segmentation of nanoparticles within various matrix materials is a difficult problem in electron tomography. Due to artifacts related to image series acquisition and reconstruction, global thresholding of reconstructions computed by established algorithms, such as weighted backprojection or SIRT, may result in unreliable and subjective segmentations. In this paper, we introduce the Partially Discrete Algebraic Reconstruction Technique (PDART) for computing accurate segmentations of dense nanoparticles of constant composition. The particles are segmented directly by the reconstruction algorithm, while the surrounding regions are reconstructed using continuously varying gray levels. As no properties are assumed for the other compositions of the sample, the technique can be applied to any sample where dense nanoparticles must be segmented, regardless of the surrounding compositions. For both experimental and simulated data, it is shown that PDART yields significantly more accurate segmentations than those obtained by optimal global thresholding of the SIRT reconstruction. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000301954300011 |
Publication Date |
2012-01-06 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
34 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
|
|
Call Number |
UA @ lucian @ c:irua:97710 |
Serial |
52 |
|
Permanent link to this record |
|
|
|
|
Author |
van den Broek, W.; Verbeeck, J.; de Backer, S.; Scheunders, P.; Schryvers, D. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Acquisition of the EELS data cube by tomographic reconstruction |
Type |
A1 Journal article |
|
Year |
2006 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
106 |
Issue |
4/5 |
Pages |
269-276 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
Energy filtered TEM, EFTEM, provides three-dimensional data, two spatial and one spectral dimension. We propose to acquire these data by measuring a series of images with a defocused energy filter. It will be shown that each image is a projection of the data on the detector and that reconstruction of the data out of a sufficient number of such projections using a tomographic reconstruction algorithm is possible. This technique uses only a fraction of the electron dose an energy filtered series (EFS) needs for the same spectral and spatial resolution and the same mean signal-to-noise ratio. (c) 2005 Elsevier B.V. All rights reserved. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000236042300003 |
Publication Date |
2005-11-30 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
6 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.843; 2006 IF: 1.706 |
|
|
Call Number |
UA @ lucian @ c:irua:56910UA @ admin @ c:irua:56910 |
Serial |
55 |
|
Permanent link to this record |
|
|
|
|
Author |
Goris, B.; Roelandts, T.; Batenburg, K.J.; Heidari Mezerji, H.; Bals, S. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Advanced reconstruction algorithms for electron tomography : from comparison to combination |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
127 |
Issue |
|
Pages |
40-47 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
In this work, the simultaneous iterative reconstruction technique (SIRT), the total variation minimization (TVM) reconstruction technique and the discrete algebraic reconstruction technique (DART) for electron tomography are compared and the advantages and disadvantages are discussed. Furthermore, we describe how the result of a three dimensional (3D) reconstruction based on TVM can provide objective information that is needed as the input for a DART reconstruction. This approach results in a tomographic reconstruction of which the segmentation is carried out in an objective manner. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000316659100007 |
Publication Date |
2012-08-02 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
63 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
|
|
Call Number |
UA @ lucian @ c:irua:101217 |
Serial |
72 |
|
Permanent link to this record |
|
|
|
|
Author |
Xu, Q.; Zandbergen, H.W.; van Dyck, D. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Applying an information transmission approach to extract valence electron information from reconstructed exit waves |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
111 |
Issue |
7 |
Pages |
912-919 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
The knowledge of the valence electron distribution is essential for understanding the properties of materials. However this information is difficult to obtain from HREM images because it is easily obscured by the large scattering contribution of core electrons and by the strong dynamical scattering process. In order to develop a sensitive method to extract the information of valence electrons, we have used an information transmission approach to describe the electron interaction with the object. The scattered electron wave is decomposed in a set of basic functions, which are the eigen functions of the Hamiltonian of the projected electrostatic object potential. Each basic function behaves as a communication channel that transfers the information of the object with its own transmission characteristic. By properly combining the components of the different channels, it is possible to design a scheme to extract the information of valence electron distribution from a series of exit waves. The method is described theoretically and demonstrated by means of computer simulations. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000300461000024 |
Publication Date |
2011-02-02 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
1 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
|
|
Call Number |
UA @ lucian @ c:irua:93623 |
Serial |
146 |
|
Permanent link to this record |
|
|
|
|
Author |
Chen, J.H.; van Dyck, D.; op de Beeck, M.; van Landuyt, J. |
|
|
Title |
Computational comparisons between the conventional multislice method and the third-order multislice method for calculating high-energy electron diffraction and imaging |
Type |
A1 Journal article |
|
Year |
1997 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
69 |
Issue |
|
Pages |
219-240 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
A1997YG59500001 |
Publication Date |
0000-00-00 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
11 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.843; 1997 IF: 1.600 |
|
|
Call Number |
UA @ lucian @ c:irua:21416 |
Serial |
455 |
|
Permanent link to this record |
|
|
|
|
Author |
Niermann, T.; Verbeeck, J.; Lehmann, M. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Creating arrays of electron vortices |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
136 |
Issue |
|
Pages |
165-170 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
We demonstrate the production of an ordered array of electron vortices making use of an electron optical setup consisting of two electrostatic biprisms. The biprism filaments are oriented nearly orthogonal with respect to each other in a transmission electron microscope. Matching the position of the filaments, we can choose to form different topological features in the electron wave. We outline the working principle of the setup and demonstrate fist experimental results. This setup partially bridges the gap between angular momentum carried by electron spin, which is intrinsic and therefore present in any position of the wave, and angular momentum carried by the vortex character of the wave, which can be extrinsic depending on the axis around which it is measured. (C) 2013 Elsevier B.V. All rights reserved. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000327884700021 |
Publication Date |
2013-10-15 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
9 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
FP7; Countatoms; Vortex ECASJO_; |
Approved |
Most recent IF: 2.843; 2014 IF: 2.436 |
|
|
Call Number |
UA @ lucian @ c:irua:112837UA @ admin @ c:irua:112837 |
Serial |
538 |
|
Permanent link to this record |
|
|
|
|
Author |
Verbeeck, J.; Bertoni, G. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Deconvolution of core electron energy loss spectra |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
109 |
Issue |
11 |
Pages |
1343-1352 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Different deconvolution methods for removing multiple scattering and instrumental broadening from core loss electron energy loss spectra are compared with special attention to the artefacts they introduce. The Gaussian modifier method, Wiener filter, maximum entropy, and model based methods are described. Their performance is compared on virtual spectra where the true single scattering distribution is known. A test on experimental spectra confirms the good performance of model based deconvolution in comparison to maximum entropy methods and shows the advantage of knowing the estimated error bars from a single spectrum acquisition. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000270765800005 |
Publication Date |
2009-07-01 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
13 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
|
|
Call Number |
UA @ lucian @ c:irua:79073UA @ admin @ c:irua:79073 |
Serial |
610 |
|
Permanent link to this record |
|
|
|
|
Author |
Kruse, P.; Schowalter, M.; Lamoen, D.; Rosenauer, A.; Gerthsen, D. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Determination of the mean inner potential in III-V semiconductors, Si and Ge by density functional theory and electron holography |
Type |
A1 Journal article |
|
Year |
2006 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
106 |
Issue |
2 |
Pages |
105-113 |
|
|
Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000234535900005 |
Publication Date |
2005-07-29 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
50 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.843; 2006 IF: 1.706 |
|
|
Call Number |
UA @ lucian @ c:irua:56143 |
Serial |
678 |
|
Permanent link to this record |
|
|
|
|
Author |
Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Filonenko, V.P.; Gonnissen, J.; Tan, H.; Verbeeck, J.; Gemmi, M.; Antipov, E.V.; Rosner, H. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Direct space structure solution from precession electron diffraction data: resolving heavy and light scatterers in Pb13Mn9O25 |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
110 |
Issue |
7 |
Pages |
881-890 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
The crystal structure of a novel compound Pb13Mn9O25 has been determined through a direct space structure solution with a Monte-Carlo-based global optimization using precession electron diffraction data (a=14.177(3) Å, c=3.9320(7) Å, SG P4/m, RF=0.239) and compositional information obtained from energy dispersive X-ray analysis and electron energy loss spectroscopy. This allowed to obtain a reliable structural model even despite the simultaneous presence of both heavy (Pb) and light (O) scattering elements and to validate the accuracy of the electron diffraction-based structure refinement. This provides an important benchmark for further studies of complex structural problems with electron diffraction techniques. Pb13Mn9O25 has an anion- and cation-deficient perovskite-based structure with the A-positions filled by the Pb atoms and 9/13 of the B positions filled by the Mn atoms in an ordered manner. MnO6 octahedra and MnO5 tetragonal pyramids form a network by sharing common corners. Tunnels are formed in the network due to an ordered arrangement of vacancies at the B-sublattice. These tunnels provide sufficient space for localization of the lone 6s2 electron pairs of the Pb2+ cations, suggested as the driving force for the structural difference between Pb13Mn9O25 and the manganites of alkali-earth elements with similar compositions. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000280050900023 |
Publication Date |
2010-04-01 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
24 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Fwo; Bof; Esteem |
Approved |
Most recent IF: 2.843; 2010 IF: 2.063 |
|
|
Call Number |
UA @ lucian @ c:irua:84085UA @ admin @ c:irua:84085 |
Serial |
721 |
|
Permanent link to this record |
|
|
|
|
Author |
Wang, A.; Chen, F.R.; Van Aert, S.; van Dyck, D. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Direct structure inversion from exit waves: part 1: theory and simulations |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
110 |
Issue |
5 |
Pages |
527-534 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
In order to interpret the amplitude and phase of the exit wave in terms of mass and position of the atoms, one has to invert the dynamic scattering of the electrons in the object so as to obtain a starting structure which can then be used as a seed for further quantitative structure refinement. This is especially challenging in case of a zone axis condition when the interaction of the electrons with the atom column is very strong. Based on the channelling theory we will show that the channelling map not only yields a circle on the Argand plot but also a circular defocus curve for every column. The former gives the number of atoms in each column, while the latter provides the defocus value for each column, which reveals the surface roughness at the exit plane with single atom sensitivity. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000279065700019 |
Publication Date |
2009-12-12 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
25 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2010 IF: 2.063 |
|
|
Call Number |
UA @ lucian @ c:irua:83691 |
Serial |
723 |
|
Permanent link to this record |
|
|
|
|
Author |
Wang, A.; Chen, F.R.; Van Aert, S.; van Dyck, D. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Direct structure inversion from exit waves : part 2 : a practical example |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
116 |
Issue |
|
Pages |
77-85 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
This paper is the second part of a two-part paper on direct structure inversion from exit waves. In the first part, a method has been proposed to quantitatively determine structure parameters with atomic resolution such as atom column positions, surface profile and the number of atoms in the atom columns. In this part, the theory will be demonstrated by means of a Au[110] exit wave reconstructed from a set of focal-series images. The procedures to analyze the experimentally reconstructed exit wave in terms of quantitative structure information are described in detail. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000304473700011 |
Publication Date |
2012-03-28 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
8 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
|
|
Call Number |
UA @ lucian @ c:irua:96660 |
Serial |
724 |
|
Permanent link to this record |
|
|
|
|
Author |
den Dekker, A.J.; Van Aert, S.; van Dyck, D.; van den Bos, A.; Geuens, P. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Does a monochromator improve the precision in quantitative HRTEM? |
Type |
A1 Journal article |
|
Year |
2001 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
89 |
Issue |
|
Pages |
275-290 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000172667000004 |
Publication Date |
2002-07-25 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
22 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.843; 2001 IF: 1.890 |
|
|
Call Number |
UA @ lucian @ c:irua:47518 |
Serial |
746 |
|
Permanent link to this record |